> in case of emergency, but its[sic] been powered off
I can't speak for Apple iPhone in particular, but I would never expect any computing device to immediately come to life and be functional if I've left it shut off and disconnected for more than two months in any case.
Most of us may be familiar with powering-up a Windows or Linux machine, and then waiting through 4 hours of updates before the system becomes available again. You would do well to power up your old hardware and let it update and connect. If only to test it for fitness of purpose. Otherwise, you shouldn't pretend that it'll be available to you in emergencies.
I can't speak for Apple iPhone in particular, but I would never expect any computing device to immediately come to life and be functional if I've left it shut off and disconnected for more than two months in any case.
Most of us may be familiar with powering-up a Windows or Linux machine, and then waiting through 4 hours of updates before the system becomes available again. You would do well to power up your old hardware and let it update and connect. If only to test it for fitness of purpose. Otherwise, you shouldn't pretend that it'll be available to you in emergencies.